Abstract
A novel lead-free Ba(1-x)(La,Na)xTiO3 (BLNT), (0 ≤ x ≤ 0.08) ferroelectric ceramic with enhanced energy storage density was fabricated by the conventional solid-state method. With an increase in La3+/Na+ content, the energy storage density, efficiency and power density were increased. The samples with (x = 0.08) show recoverable energy storage of (1.07 J/cm3), 3 times higher than that of pure BaTiO3 ceramics, energy storage efficiency of (87.6%) and power density of 0.314 MW/cm3, 17 times greater than that of pure BaTiO3 ceramics. Comparison with other lead-free ferroelectric ceramics confirmed the superiority potential of (BLNT-0.08) ceramics for the design of ceramics capacitors for energy storage applications. The effect of La3+/Na+ contents on the optical properties of BaTiO3 ceramics was studied via UV spectroscopy. The results revealed that the introduction of structure disorder by means of A-site vacancies leading to the creation of shallow defects resulting in narrowing the bandgap energy. This work may provide a simple and powerful method to develop inexpensive energy storage and photovoltaic devices based on ferroelectric ceramics.
Acknowledgments
The authors are greatly indebted to the Sao Paulo Research Foundation (FAPESP) (grant no# 2019/03110-8) for financial support.